Los Blancos are thought to be keen on Manchester United shot stopper David De Gea after Madrid missed out on the Spain international in last summer’s transfer window.
However, Jose Mourinho’s imminent appointment as United manager means De Gea could remain at Old Trafford despite a lack of Champions League football next season.
Courtois, who previously spent three years at Atletico Madrid, has been heavily linked with a return to the Spanish capital in the white of Real.
Sky Sports’s La Liga expert Balague believes Courtois is a legitimate target for Madrid amid reports the Blues want £50m for the Belgium number one.
“Somehow I don’t think Jose Mourinho and Cristiano Ronaldo will ever cross paths again. The relationship broke down when they were at Real Madrid and I’m not sure that will be rekindled,” Balague told Sky Sports.
“There’s clearly an offer from PSG to get Ronaldo. It’s a high offer but maybe not high enough for Real Madrid.
“There’s a private agreement between Jorge Mendes and PSG for Ronaldo to go to France but if Real don’t feel there is anyone of that calibre in the market, not only will they keep him but they may actually renew his contract for a couple more years.”
Courtois has won the Premier League and the League Cup since his return to Chelsea in 2014.
The Belgium international won La Liga and the Europa League with Atletico under Diego Simeone.
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